In this paper, by using a mathematical model, potential for power generation of a Solar Chimney Power Plant (SCPP), has been studied in Semnan city conditions. Conceptual model of solar chimney power plant was developed. Governing equations were developed for a solar chimney power plant based on the conceptual model. The iteration technique (try and error) is applied for solving the mathematical model. Mathematical model was validated by experimental data obtained from Manzanares plant and also data existed in the literature. Then model was run for different weather conditions in Semnan city. Given results showed that generated power in Semnan city conditions is lower than in Manzanares plant at the different selected times. In April this power plant produces power of 49 kW. When inlet temperature at collector inlet is increased 5 °C, the generated power of plants is decreased approximately by 3%. Among the geometric dimensions of the plant, Chimney height has the most influence on generated power. Also it was found that radiation has the most influence on power plants performance.